Overshot apparatus for manipulating a bridge plug in a well



K. W. BEVER OVERSHOT APPARATUS FOR MANIPULATING A BRIDGE PLUG IN A WELL Filed Sept. l1. 1968 3 Sheets-Sheet 1 FIG. I0

INVENTOR KENNETH W. BEYER @www ATTORNEYS Marsh 17, 1970 K W. BEYTER 3,500,909

OVERSHOT APPARATUS FOR MANIPULATING A BRIDGE PLUG IN A WELL Filed Sept. l1, 1968 l 5 Sheets-Sheet 2 FIG. 2 lol 97 L FIG. 5

68 854i( I: l

HG. 4 www KENNETH W. BEY ER ATTORNEYS,

OVERSHOT APPARATUS FOR MANIPULATING BRIDGE PLUG IN A WELL Filed Sept. l1, 1968 K. W. BEYER I Mmh 17, 1970 3 Sheets-Sheet 3 M l 'j ATTORNEYS:

United States Patent O 3,500,909 OVERSHOT APPARATUS FOR MAN IPULATING A BRIDGE PLUG IN A WELL Kenneth W. Beyer, Powell, Wyo., assignor to Halliburton Company, Duncan, Okla., a corporation of Delaware Filed Sept. 11, 1968, Ser. No. 759,033 Int. Cl. E211) 23/06 U.S. Cl. 166--134 4 Claims ABSTRACT OF THE DISCLOSURE An overshot tool for use in a well bore to transport and test the setting of a bridge plug. The overshot tool includes a pair of circumferentially and longitudinally displaced control slots. An L-shaped guide means extends between the two control slots and defines a portion of the boundary of a generally unimpeded transition zone. A pair of mutually converging guide surface -means provides an entry path leading into the transition zone, with one of the lguide surface means extending longitudinally of a well bore.

GENERAL BACKGROUND, OBJECTS AND SUMMARY OF INVENTION In recent years, a retrievable bridge plug has been developed which operates in a uniquely simple but effective manner.

The bridge plug is characterized by a body which support uid responsive seal means. The seal means projects outwardly of the body and provides a sliding, piston-like seal between the body and the wall of a well bore. A slip assembly is telescopingly mounted on the exterior of the body. Relative movement between the body and the slip assembly serves to wedge the body into fixed position within a well bore. The body movement, which induces this wedging action, results from a iiuid pressure differential extending longitudinally across the body within the well bore and acting upon the seal means.

A particularly efticient bridge plug of this type is described, for example, on page 137 of the Halliburton Sales and Service Catalog (1968) published by Halliburton Services of Duncan, Oklahoma.

A bridge plug, as above described, may be transported through a well bore by a conduit string, with a cylinder slot and mandrel lug assembly providing a detachable connection between the conduit string and the bridge plug. In the past, fairly complex slot and lug structures have been proposed for use in connection with the transporting and and manipulating of a bridge plug as above descri-bed. For example, in the United States'Baker Patent 2,776,012 and the United States Crowe Patent 2,998,072, highly complex slot structures are featured which require zigzag manipulations of a conduit string.

The overall character of these zigzag slot patterns is such as to make it ditlicult for an operator, at a well head, to always be sure of the position of a mandrel lug within the control slot pattern.

The overall complexity of these zigzag slot patterns complicates the operation of interconnecting and disconnecting the control slot from the mandrel lug means.

Further, the essentially linear, but zigzag configuration, of the Baker and Crowe control slots provide only limited opportunities for an operator to apply force to a mandrel, through a conduit string, so as to effect the desired positioning'of the mandrel within the bridge plug itself.

The zigzag slot pattern inherently creates a tendency for a conduit string to induce bridge plug rotation while an operator is attempting to manipulate the control slot, without intending to introduce such undesired bridge plug movement. Complicating this potential for effecting undesired bridge plug rotation, is the inability of the control 3,500,909 Patented Mar. 17, 1970 ICC slot structures featured in the aforesaid Baker and Crowe patents to rotate in opposite directions about the axis of the bridge plug in the event that operating difliculties should develop.

Further, due to the absence of appropriate barriers between portions of the zigzag slot pattern of the Baker and Crowe structures, it is quite possible for an operator to inadvertently position mandrel lug means of the bridge plug in an incorrect control slot position.

Recognizing the need for a bridge plug transporting and manipulating structure having improved operating characteristics, it is an object of the present invention to provide such an apparatus which substantially eliminates or minimizes problems of the type above described.

It is a particular object of the invention to provide a control slot pattern which operates, in conjunction with a mandrel of the bridge plug of the type above described, to enable the setting of a bridge plug to be tested with minimized manipulative effort and with an operator having greater assurance as to the relative positioning which exists between a control slot and a mandrel lug.

It is another object of the invention to provide such an improved apparatus which provides an L-shaped guide surface which ensures ease of movement between two circumferentially and longitudinally spaced control slots, and while enabling an operator at all times to be sure of the position of the control slots relative to -mandrel lug means.

It is a further object of the invention to provide such an improved apparatus which is characterized by a substantially simplified movement between a control slot and mandrel lug in order to effect manipulations of a bridge plug.

Yet another object of the invention is to provide such an improved apparatus which is characterized by a lug entry arrangement which enables a simple, longitudinal movement of the control slot to move a mandrel lug into, or out of, a circumferentially extending and unimpeded transition zone extending between the aforesaid control slots.

It is still an additional object of the invention to provide such an improved apparatus wherein an upper wall of the transition zone, which defines a portion of the L- shaped guide means, operates as a circumferentially extending force transmitting surface operable throughout the circumferential spacing between the two control slots.

It is also an object of the invention to provide such an improved apparatus characterized by uninterrupted guide surfaces which provide positive barriers, deterring the inadvertent entry of a mandrel lug into an undesired slot portion.

A still further object of the invention is to provide such an improved apparatus which is characterized by a control slot which may be selectively manipulated in either of opposite rotary directions about an axis of a well bore so as to permit any desired rotarymovement of an actuating conduit string, while eliminating protrusions in the control slot pattern which might engender inadvertent or undsired rotation of the mandrel and its associated bridge p ug.

In accomplishing at least some of the foregoing 0bjects, there is presented through the invention an apparatus characterized by unique transporting means for -moving a well tool means through a well bore.

The transporting means includes body means having a longitudinal axis disposed to extend generally longitudinally of a well bore in which the apparatus is located.

The body means is operable to detachably engage lug means carried by the well tool means. A first slot means carried by the body means is operable to telescopingly receive the lug means. This slot means is disposed to extend generally longitudinally of the well bore. A second ;lot means also carried by the Ibody means, is operable to :elescopingly receive the lug means. This second slot neans is also disposed to extend generally longitudinally )f the well bore.

A generally L-shaped guide means extends between the irst and second slot means. This generally L-shaped guide neans includes uninterrupted, first guide means extending generally circumferentially of the longitudinal axis of the )ody means. This rst guide means is generally aligned vith a plane extending transversely of the longitudinal txis of the body means. The generally L-shaped guide neans further includes uninterrupted, second guide means extending generally longitudinally of the well bore and lownwardly from the first guide means, when the appaatus is disposed in the well bore. This second guide means :xtends directly into the second slot means.

The first guide means provides uninterrupted guide neans, operable throughout its entire circumferential exent, to transmit force from the operating means to the ug means, with this transmitted force being operable to nduce movement of the lug means.

An uninterrupted third guide means extends generally ongitudinally of the well bore. An uninterrupted fourth guide means, displaced circumferentially from the third neans, converges continuously toward the third guide neans. Means included in the apparatus permits generlly unimpeded relative rotational movement between the rody means and the Well tool means, with movement of he lug means relative to the second and third guide means |ccurring along a path generally aligned with the aforeaid plane which extends transversely of the axis of the rody means.

The novelty of this basic combination is augmented y specific geometric relations between the guide means nd slot means and a rigid connection between the transorting means and a conduit string. This rigid connection nables selective, and oppositely directed, rotary movement f the transporting means to be effected.

DRAWINGS In describing the invention, reference will be made to preferred embodiment shown in the appended drawings.

In the drawings:

FIGURE la provides a schematic illustration of a bridge rlug, of the type above described, as it is being lowered hrough a well bore, with a control mandrel affirmatively reventing wedging cooperation between a slip assembly nd a slip expanding surface carried by a bridge plug dr;

FIGURE lb schematically illustrates the FIGURE la ssembly while a transporting cylinder is being manipuated to test the setting or wedging in place of the bridge lug;

FIGURE 1C schematically illustrates the retrieving of he FIGURE 1abridge plug;

FIGURES 1d, le and 1f illustrate in fragmentary and chematic format, the positional relationships which exist `etween a mandrel lug and a conduit-string-carried, conrol slot in relation to FIGURES la, lb' and lc, respecively. Each control slot shown in FIGURES 1d to 1f' is iewed from the exterior of the conduit string supported ylinder which defines the slot, as though the cylinder vall in which the slot is formed were attened;

FIGURE 2 provides an enlarged plan view of the conrol slot pattern shown in FIGURES la through 1f, where single control slot having a circumferential extent of 60 is employed. The FIGURE 2 control slot is viewed s though the cylinder wall dening the control slot were lattened, with the slot being viewed from the exterior if the cylinder which denes the slot;

FIGURES 3cr, 3b and 3c, joined at connecting lines v --a and b-b provide an enlarged, vertically sectioned, llustration of the packer assembly and control slot carry- 1g cylinder of the FIGURE la bridge plug, with the bridge lug transporting and manipulating assembly including a 4 pair of diametrically oppositely located slots of the type shown in FIGURES ld through lf;

FIGURE 4 provides a still further enlarged, transverse sectional view of the FIGURE 3a-3c assembly as viewed along the section line 4 4 of FIGURE 3b; and

FIGURE 5 provides a transverse sectional view of a slip disabling mandrel portion incorporated in the FIG- URE 3a-3c assembly, as viewed along the section line 5 5 of FIGURE 4.

MAI OR COMPONENTS OF APPARATUS FIGURES 1a through lf illustrate major components of the apparatus of this invention.

As illustrated, the overall apparatus 1 comprises a bridge plug 2. Bridge plug 2 is detachably supported on the lower end of a conduit or well string 3 by a cylinder-like sleeve 4.

Conduit string 3 extends upwardly, through a well bore 5 in which the apparatus 1 is positioned, to a well head, not shown.

Bridge plug 2 includes a generally tubular, central body 5. A cylinder-like slip assembly 7 is telescopingly mounted on the exterior of a median portion of the body 6. A central, rod-like mandrel 8 passes telescopingly through a central passage 9 of the body 6.

At its upper end, mandrel 8 is provided with a receiving head 10. One or more lugs 11 project generally radially outwardly of the receiving head 10. As shown in FIGURE 1d, for example, each such lug 11 may be longitudinally elongate in vertical cross section.

Transporting unit or cylinder `4 is provided with one or more control slots 12. Each such control slot 12 individually and telescopingly receives a lug 11.

In the embodiment shown in FIGURES la through lc, the cylinder 4 is provided with a single control slot 12 and the receiving head 10 is provided with a single lug 11.

In the embodiment shown in FIGURE 3a, a pair of circumferentially spaced and diametrically oppositely located slots 12 are incorporated in the cylinder 4. In this embodiment, the two diametrically oppositely projecting lugs 11 are provided with each such lug 11 being individually associated with a single slot 12. The slots 12 are cir-v cumferentially spaced so as to be mutually isolated from each other, i.e., the two slots 12 are separated by solid cylinder wall segments.

In the FIGURE 3a embodiment, the two lugs 11 operate in association with their slots 12 in an identical fashion and in unison.

STRUCTURE AND MODE OF OPERATION OF BRIDGE PLUG Structural details of the bridge plug 2 are illustrated in detail in FIGURES 3cr, 3b, 3c, 4 and 5.

Bridge plug b ody structure As previously noted, bridge plug 2 includes a generally tubular body 6, a slip assembly 7, a central mandrel 8, and a body passage 9 which telescopingly receives the mandrel 8.

Body 6 includes generally, or at least partially, tubular segmentn 13, 14, 15, 16, 17, 18 and 19 which are threadably interconnected at coupling junctions 20, 21, 22, 23, 24 and 25.

Component 17 provides a downwardly facing and converging and generally frustoconically configured, slip expanding surface 26. Components 17 cooperates with component 19 to provide a shoulder-like recess 27. A uid responsive, elastomeric, cup and packer ring assembly 28 is supported on shoulder 27. Assembly 28 includes an annular, piston-like lip 29 which is operable to deflect downwardly and radially outwardly in response to a pressure differential acting longitudinally within the well bore 5 across the lip 29, with a higher pressure existing above the lip 29 than below this lip. In this connection, it will be understood that the bridge plug 2 will be dimensioned so that when it is lowered into the well bore 5, the outermost periphery 30 of the deflectable lip 29 will slidably engage the wall of the well bore 5 so as to enable such a pressure differential to effect this lip deflecting action.

At the lower end of the body 6, component provides an upwardly facing and converging, and frustoconically configured, slip expanding surface 31.

Components 14 and 15 cooperate to define an annular shoulder or recess 32 upon which an elastomeric cup and packer ring assembly 33 is supported.

Assembly 33 provides an elastomeric and fluid responsive, piston-like annular seal or lip 34 extending outwardly and downwardly from the assembly 33. Lip :i4-includes an outermost portion 35 adapted to slidably and sealingly engage th'e wall of a well bore 5 into which the plug 2 is inserted.

A pressure differential acting longitudinallyacross the lip 34, with a greater pressure existing below the lip 34, will cause the lip 34 to deflect outwardly and upwardly into tight sealing engagement with the wall of the well bore 5.

As will be appreciated, each of the lips 29 and 34 provides an annular, piston-like, fluid responsive seal extending between the tool body 6 and the wall of the well bore 5. A higher fluid pressure existing in a well bore above the pug than below the plug operates in conjunction with the lip 29 so as to tend to move the plug body 6 downwardly in a well bore. Conversely, a higher fluid pressure in a well bore 5 below the lip 34 than above this lip will operate in conjunction with the lip 34 to tend to move the plug body 6 upwardly within the well bore.

Although the fluid responsive, piston defining lips 29 and 34 provide means for moving the body 6 within a well bore 5 in response to fluid pressure differentials, it is necessary to provide some significant but yieldable resistance to movement of the body 6 relative to the telescoping mandrel 8. To this end, the lower components 13 of the body is provided with one or more, radially outwardly projecting, drag springs 36. Drag springs 36 are connected to conventional threaded fastening means 37 to the segment 13. These drag springs serve to frictionally engage the wall of the well bore 5 so as to somewhat impede movement of the body 6, relative to the conduit string 3 and mandrel 8, when these components are interconnected by the cylinder 4 and receiving head 10.

Slip structure The slip assembly 7 includes a generally tubular body 38. A plurality of circumferentially spaced drag springs 39, as shown in FIGURES 3b and 4, project radially outwardly of the slip assembly body 38. These drag springs 39, which are conventionally mounted and of well recognized structure, frictionally engage the wall of the well bore 5 so as to impede movement of the slip assembly 7 relative to the body 6.

Thus, when the body 6 is caused to move longitudinally of the well bore 5, as a result of the above-described pressure differential action, the drag springs 39 serve to at least temporarily, but yieldably, immobilize or impede movement of the slip assembly 7.

Slip assembly 7, at its upper end, supports a plurality of conventional slip segments 40. Each of such slip segments 40 includes a pivotally supported lower end 41 and a retaining spring 42. Thus, the upper end 43 of each segment 40 is operable to pivot or move outwardly into wedging or gripping engagement with the wall of the Well bore 5. This pivoting action, or outward displacement of the slipsegments 40, is effected as a result of the downward movement of the body 6 so as to cause the slip expanding surface 26 to simultaneously and cammingly engage the upper ends 43 of the slip segments. This camming engagement forces the slip segments radially outwardly into wedging or tight-fitting cooperation between the surface 26 and the wall of the well bore 5 so as to lock the body 6 in position within the Well bore.

This mode of wedging engagement occurs when the fluid pressure differential acts on the piston-like lip 29 so as to move the body 6 downwardly.

The lower end of the slip assembly 7 is provided with another series of circumferentially displaced, slip segments 44. The lower ends 45 of slip segments 44 are pivotally secured, by conventional means, to the slip assembly body 7. Arcuate retaining springs 46, identical to springs 42, are each connected at one end 47 to the body 7 with a free end 48 yieldably and restrainingly engaging an individual slip segment 44.

Thus, upward movement of the body 6, induced by a fluid pressure differential effectively acting on the pistonlike lip 44, will cause the camming surface 31 to move the lowermost or free ends 49 of the slip segment 44 radially outwardly into wedging cooperation between the surface 31 and the wall of the well bore 5.

Thus, in response to either a downwardly effective or upwardly effective fluid pressure differential within the well bore 5 acting longitudinally across the body 6, the body 6 will move longitudinally so an to induce a selfsetting or self-wedging action.

Mandrel structure Mandrel 8 includes a series of threadably interconnected, rod-like sections 50, 51 and 52 interconnected at threaded junctions 53 and 54. Uppermost rod section 52 is threadably connected to a solid, rod-like receiving head 10 by threaded junction 55.

At the upper end of the body 6, a generally annular check valve 56 is telescopingly mounted on the rod segment 52. Check valve 56 is biased by a coil spring 57 into seating engagement with a frustoconical valve seat 58 formed in the body segment 19. One or more circumferentially spaced, and radially outwardly projecting, slots 59 are formed in the body segment 19. These slots 59 provide fluid communication between Well bore fluids and the central passage 9 when the valve member 56 is displaced upwardly out of seating engagement with the seat 58. As illustrated, the upper end of the coil spring 57 is secured by an annular abutment 60 mounted on the segment 19, and through which the rod segment 52 telescopmg passes.

At the lower end of the mandrel 8 an annular check valve 61 is telescopingly mounted on the exterior of mandrel segment 50. Check valve 61 is biased upwardly into seating engagement with a valve seat 62 formed on the body segment 13. Valve 61 is biased against the frustoconical seat 62 by a coil spring 63. The lower end of the coil spring 63 is secured in place by annular abutment 64 carried by segment 13. As shown, mandrel 8 passes telescopingly through this abutment 64.

One or more longitudinally extending openings 65, schematically shown in FIGURE 3c, provide fluid communication between fluids in the well bore 5 beneath the bridge plug and the passage 9, when the valve member 61 is displaced downwardly out of seating engagement with the seat 62.

As illustrated, the valve members 61 and 56 cooperate with annular abutments 66 and 67, formed by coupling portions 53 and 54 respectively, to resiliently and longitudinally center the mandrel 8 within the body 6.

The seated valve members 61 and 56, in cooperation with the lips 29 and 34, serve to transversely seal the well bore 5. As will thus be appreciated, with each of the valves 56 and 61 seated, and with the seals 29 or 34 engaging the wall of a well bore, the bridge plug 2 is effective to isolate the portion of a well bore beneath the plug from the portion of the well bore above the plug.

Mandrel 8 is provided with a cross bar 68. As illustrated, cross bar 68 is afilxed to mandrel component 51 and projects radially outwardly through identical, but diametrically opposite, slots 69 and 70 of body segment 16. Cross bar 68 also projects radially outwardly through :liametrically opposite, but identical, slots 71 and 72 formed in slip assembly body 38.

As illustrated, slots 69 and 70 are somewhat greater in .ength than slots 71 and 72.

In a manner now well recognized in the art, movement )f the mandrel means 8 downwardly will cause the lower iurface 73 of cross bar 68 to abuttingly engage the lower ends 74 and 75 of slots 71 and 72 and move these ends 74 and 75 into planar alignment with the lower ends 76 and 77 of slots 69 and 70.

This alignment of slot lower ends will serve to position :he slip segments 40 downwardly, out of camming cooperation with the surface 26, and will additionially cause the abutment 66 to move the valve 61 downwardly away from :he valve seat 62. Thus, by moving the mandrel means 8 lownwardly relative to the body means 6 and the slip assembly 7, the tendency for the slip ysegments 40 to set is nbviated and upward fluid flow through the held-open valve 61 and the upwardly opening check valve 56 is pernitted. Thus, the depression and lowering of the mandrel neans 8 relative to the bridge plug body and slip assembly enables the bridge plug to be lowered into a well bore avithout slip setting taking place and without causing the bridge plug to function as a swab or piston.

Conversely, upward movement of the mandrel means 8 relative to the body 6 and slip assembly 7 will cause the ipper surface 78 of the cross bar 68 to abuttingly engage the upper ends 79 and 80 of slots 71 and 72 and move these slot upper ends into planar alignment with the upper :nds 81 and 82 of the slots 69 and 70. With this alignment 3f slot upper ends, the lower slip segments 44 arel moved lpwardly out of wedging cooperation with the slip exsanding surface 31. Additionally, the valve 56 is moved to in open position so as to permit a downward flow of fluid :hrough the held-open valve 56 and the downwardly open- ,ng check valve 61. Thus, during the retrieving or raising 3f the bridge plug 2 through well bore 5, upward movenent of the mandrel means 8 relative to the plug body 6 1nd the slip assembly 7 will prevent slip wedging action and provide an open flow passage 9 so as to ensure that :he bridge plug 2 does not act as a swab or piston.

As illustrated in FIGURE 4, cross bar 68 maybe sta- Jilized by an enlarged T-shaped end 83 mounted in an enlarged, radially outermost slot portion 84 of slot 71. The heads 85 of threaded fasteners 86 providedetachable I`head means to secure the other end of the cross bar 68 in an enlarged, radially outermost, slot portion 87 of slot 72.

With the overall structure and mode. of operation of the )ridge plug 2 having been described, it now becomes appropriate to consider the manner in which the cylinder 4, with its slot means 12, cooperates with the receiving 'lead 10 and its lug means 11 to elfe-ct the transporting 1nd manipulating of the bridge plug 2.

STRUCTURE OF BRIDGE PLUG TRANSPORTING AND MANIPULATING MEANS The apparatus for effecting the running, retrieving and testing of the bridge plug 2 comprises the cylinder 4 with .ts slot means 12, which cylinder means is supported by :he conduit string 3. This apparatus further includes the receiving head of the mandrel 8 and the lug means 11.

It is the cooperation between the lug means 11 and the slot means 12 which determines the manner in which the bridge plug 2 is manipulated by the conduit string 3.

In this connection, it will be readily understood that the conduit string 3 is lowered or raised, and rotated selectively in either of opposite rotary directions about the Well bore axis, by conventional conduit string hoisting and rotating means (not shown). Such hoisting and rotating means would be located at the well head (also not shown).

It will also here be appreciated that cylinder 4 is rigidly connected to the conduit string 3 by a conventional, threaded coupling means 88. In this manner, rotary movement of the conduit string 3, either clockwise or counterclockwise about the bore. hole axis, will serve to induce corresponding directional rotation of the cylinder 4.

Throughout the ensuing discussion, reference will be made to the cooperation between a single lug 11 and a single guide slot 12 associated with this lug. Obviously, this discussion will suffice to explain the operation of the preferred embodiment shown in FIGURE 3a which includes a pair of guide slots 12 and a pair of lugs 11 and will also suice to explain the operation of the arrangement shown in FIGURE la including a single guide slot and lug.

Whether the apparatus includes a pair of guide slots and lugs, or a single guide slot and lug, each guide slot 12 will be configured substantially as shown in FIGURES la and 1f and FIGURE 2.

Thus, each guide slot 12 includes a first slot means 89 which is operable to telescopingly receive a lug 11. Slot 89 extends longitudinally of the bore hole 5 and serves to permit longitudinal movement of the cylinder 4, relative to the mandrel lug 11, when the lug 11 is positioned within the slot 89. However, when the lug 11 is positioned in the slot 89, relative rotational movement between the lug 11 and the slot 89, to any significant degree, is prevented.

Slot 12 also includes a second slot means 90, displaced both lcircumferentially and longitudinally from the first slot means 89. The second slot means 90 extends longitudinally of the bore hole and cylinder 4. Slot means 90 is operable to permit longitudinal telescoping movement of the cylinder 4 Irelative to the lug 11 when the lug 11 is received in the slot 90. However, the width of the slot 90 is only slightly less than the width of the lug 11 such that, with the lug 11 received in the slot 10, relative rotary movement between the cylinder 4 and the lug 11 is substantially prevented.

As illustrated, slot 90 is disposed generally beneath the slot 89, when the cylinder 4 is disposed in the well bore 5. Slot 90 extends downwardly to terminate in a closed lower end 91 while slot 89 extends upwardly to terminate in a closed upped end 92. Slot 90 has an upwardly facing ent-ry mouth 93 while slot 89 has a downwardly facing entry mouth 94.

A generally L-shaped guide means 95 extends between the first and second slot means 89 and 90.

Guide means 95 includes a rst, uninterrupted, arcuate and circumferentially extending guide face 96. This rst guide means 96 intersects the wall 97 of slot 89, and is generally aligned with a plane extending transversely of the longitudinal axis of the cylinder 4. This plane may extend perpendicularly to the longitudinal cylinder axis, as shown in FIGURE 2, or may be slightly inclined so as to extend upwardly away from wall 94 at an inclinat1on of about five to ten degrees, or less, with respect to a plane extending perpendicular to the longitudinal cylinder axis.

In this connection, it will be appreciated that the first gu1de means 96 is arcuate in nature and the inclination here referred to is that which would result from the cylinder 4 being laid at or developed.

L-shaped guide means 95 further includes an uninterrupted, second guide means or surface 98. Guide means 98 .extends longitudinally of the longitudinal axis of the cylinder 4 and in the preferred embodiment extends parallel to this cylinder axis. Guide means 98 extends directly into the second slot means 90 and defines a continuation of side wall 99 of slot 90.

At this point, it will be appreciated that slot 90 s characterized by parallel side walls 99 and 100, and slot 89 is characterized by parallel side walls 97 and 101.

The guide means 96 provides a guide surface operable throughout its entire circumferential extent to transmit longitudinally applied, and downwardly directed, force from the conduit string 3 through the cylinder 4 and lug 11 to the mandrel 8.

The upper end 92 of slot 89 is located such that, as shown in FIGURES le and lb, the cylinder 4 may be depressed to cause the lower cylinder edge 102 to abuttingly engage the upper extremity 103 of the bridge plug body means 6, with the lug 11 being disposed within the slot 89 but spaced from the upper slot end 92. With this arrangement, downward force may be applied directly t-o the bridge plug body 6 without movement inducing force being applied to the mandrel 8.

In the absence of force applied to the mandrel 8, the springs 63 and 57 will cooperate, through the structure of the valves 56 and 61 and the abutments 67 and 66, to maintain the cross bar 68 in the neutralized or inoperable position shown in FIGURE 5.

Guide surface 96 is located such that, as shown in FIGURES la and 1d, with the lug 11 engaging the surface 96, downward force may be applied to the mandrel 8, through the lug 11 so as to move the mandrel downwardly. This downward mandrel movement will move the slip segments 40 out of cooperating relationship lwith the slip expanding surface 26 and open the check valve 61.

Slot 90, and its lower terminus 91, is located so as to enable the converse disabling position of the mandrel 8 to be effected when a raising force is exerted on the conduit string 3. Thus, with the conduit string 3 raised and the lug 11 disposed in the slot 90 and engaging the slot terminus 91, the mandrel means 8 may be raised to the position shown in FIGURES 1c and 1f. In this position, the raised mandrel 8 has effected the moving of the segments 44 to a position displaced from cooperating relation from the slip expanding surface 31. In addition, the upper check valve 56 will have been moved to an open position.

Slot means 12 additionally includes a downwardly facing, lug entry mouth 104. Mouth 104 is disposed longitudinally beneath the slot 89 when the cylinder 4 is disposed in the well bore 5.

Slot means 12 additionally includes uninterrupted, third grade means 105. This guide means or surface 105 eX- tends longitudinally upwardly from the mouth 104, lwhen the cylinder 4 is in the well bore 5. In the preferred embodiment, guide surface 105 is disposed in -parallel alignment with the longitudinal axis of the cylinder 4.

Uninterrupted, fourth guide means or surface 106 extends circumferentially or arcuately from the mouth 104 and generally upwardly away from this mouth. In the laid flat or development view of the slot means 12, this fourth guide surface 106 is linear in nature and converges continuously toward the linear and vertically extending, third guide means or surface 105.

lEach of the third and fourth guide means 105 and 106, respectively, terminate above the base 91 of the sot 90 when the cylinder 4 is located in the well bore 5.

A generally rectangular transition zone 107 is located longitudinally between the mouth 104 and the control slot portion 89. This transition zone is interally unimpeded and is defined, in part, by guide surfaces 96, 98 and 105.

The complete absence of impeding structure between the third guide surface 105 and the second guide surface 98 enables the cylinder 4 to be rotated relative to the mandrel 8 so as to enable the lug 11 to undergo movement relative to the cylinder 4 along an unimpeded path. This path may be viewed as being generally aligned with the plane extending transversely of the longitudinal cylinder axis and coextensive with the first guide surface 96.

The lower end of transition zone 107 is defined by the guide slot 90 and the wall 108 which extends arcuately and upwardly from the slot side wall 100 to a slot throat 109. A generally longitudinally or vertically extending slot wall portion 110 interconnects the wall 108 and the fourth guide surface 106 to provide continuity in the slot peripheral configuration. A similar arcuate connecting wall 111 serves to provide slot periphery continuity between the guide surface 105 and the wall 101 of slot 89.

As will thus be appreciated, the control slot 12 is defined by an uninterrupted periphery so as to ensure that the lug 11, when positioned within the longitudinal confines of the slot 12, is completely controlled as to its manipulations by the manipulations of the single slot means 12.

As shown in FIGURE 2, where a single guide slot 12 is employed, and where the mouth 104 extends for a fully circumferential extent of 360, it is appropriate to provide a centering pad 112. Centering pad 112 may be more or less square in conguration and oriented as Shown in FIGURE 2 so as to provide upwardly diverging guide surfaces 113 and 114.

Guide pad 1.13 includes a radially innermost periphery which is operable to engage the radial periphery 115 of the receiving head 10 so as to axially center the receiving head 10 as it enters the entry mouth 104. The lug 11 may pass through the entry mouth 104 to the throat 109 by passing through either of the throat zones .116 or 117 circumferentially disposed on opposite sides of the centering pad 112.

As will be appreciated, this centering action results from the pad 112 engaging one side of the periphery 115 of the receiving head 10, with unslotted, radially inwardly facing peripheral portions 118 of the cylinder 4 engaging the other side of the periphery 115.

This centering action ensures that the receiving head enters the cylinder 4 without causing the lug 11 to abuttingly engage the edge 102 of the cylinder 4. The centering action also causes the receiving head to enter the Slot 12 so as to avoid off-center jamming of the lug 11 relative to unslotted internal portions of the cylinder 4.

OVERALL OPERATION OF APPARATUS The overall operation of apparatus 1 is schematically illustrated in FIGURES la through 1f.

Bridge plug lowering FIGURE la illustrates the disposition of components as the bridge plug 2 is being lowered through the well bore 5 on the lower end of the conduit string 3.

During this lowering or runningdn operation, the lug 11 is disposed in abutting engagement with the rst guide surface 96. With this position of the lug 11, a downward force on the conduit string 3 depresses the mandrel 8 and slip assembly 7 relative to the drag spring restrained bridge plug body 6. This depressing movement of the mandrel 8 and slip assembly 7 will Iplace the upper slip segments 40 out of wedging cooperation with the slip expanding surface 26 so as to enable the free or unimpeded lowering of the bridge plug 2.

In this connection, it will be appreciated that lower Slip segments 44, during the tool lowering. movement will not tend to wedgingly cooperate with the lower slip expanding surface 31. Any frictional force acting on the segments 44, as a result of these segments engaging the wall of the well bore 5, will merely tend to move the slips 44 out of wedging cooperation with the surface 31.

Thus, in the FIGURE 1a arrangement, lowering force is transmitted from the conduit string 3 through the mutually abutting slot 96 and lug 11 to force the bridge plug downwardly through the well bore. It is signicant to here note that substantial relative rotation may occur between the cylinder 4k and the bridge plug 2, while maintaining the downward force acting on the bridge plug, but without applying or imparting a rotational force to the mandrel 8. Thus, the lug 11 may translate about the axis of the cylinder 4 and along the surface 96 in either of opposite rotary directions while still imparting lowering force to the bridge plug and without causing mandrel rotation.

Bridge plug setting and testing After the bridge plug has been lowered to the desired position within the. well bore S, it is appropriate for an operator to determine if the fluid pressure differential 11 existing in the well bore has been sufficient to induce the setting of the bridge plug.

FIGURE lb illustrates the testing operation where a greater fluid pressure exists above the bridge plug 2 rather than below the bridge plug. This greater uid pressure above the bridge plug may have been created by pressurizing uid in the well annulus above the plug 2 so as to provide a pressure differential force acting on the lip 29 sufficient to move the plug body downwardly and cause the slip segments to be wedged between the expanded surface 26 and the wall of the well bore 5.

Assuming that the bridge plug 2 has been set in this manner, the operator, in order to test the successful setting, will impart righthand or clockwise rotation to the cylinder 4 so as to move the lug 11 to the vicinity of the guide surface 105. By then imparting downward force to the conduit string 3, the lug, in essence, will be caused to translate along the surface 111 and into the slot I89. Continued downward movement of the conduit string 3 will cause the cylinder end 102 to abuttingly engage the upper end 102 of the bridge plug body. This abutting engagement will occur before the lug 11 engages the upper extremity 92 of the slot 89.

In this manner, the mandrel 8 will remain in its neutralized or centered position shown in FIGURES 3a through 3c, i.e. positioned so as not to interfere with the wedging action of the slips 40 and positioned so as not to open either of the valves 56 or 6.1.

If the bridge plug has set properly, the engagement between the cylinder end 102 and the bridge plug eX- tremity 103 will be detected at the well head by a decrease in effective weight of the conduit string 3. This substantial decrease in apparent conduit string weight will indicate that the bridge plug has been wedged or set.

It will here be understood that this same testing procedure may be effectively applied when the pressure beneath the bridge Iplug 2 exceeds the pressure above the plug, so as to have moved the plug body upwardly and caused the segments 44 to provide the bridge plug wedging or setting action. vIt will also be apparent that this testing procedure may, in some instances, be used to cause setting of the bridge plug in the FIGURE lb position.

After the bridge plug has been tested and found to have been satisfactorily set, the operator needs merely to apply continued righthand or clockwise rotation to the conduit string 3 while raising the string. This will cause the lug 11 to move downwardly along the slot surfaces 111 and 105 and out of the slot entry mouth 104. In this manner, the mandrel 8 and cylinder 4 will disengage so as to permit the raising of the conduit string 3 and cylinder 4 away from the set bridge plug 2.

It is here significant to note that this detaching action involves, for the most part, a simple lifting or vertical movement so as to enable the lug to translate vertically along the guide surface 105.

By applying the simple manipulations above noted, it is highly unlikely that an operator would inadvertently relocate the lug 1.1 in the lower slot 90 and inadvertently unset the bridge plug.

Bridge plug retrieving Bridge plug 2 may be retrieved by lowering the cylinder 4 and conduit string 3 so as to cause the receiving head 10 to reenter the open ended interior of the cylinder 4. This entry is effected by adjusting the rotational position of the cylinder 4 so that the lug 11 enters the entry zone 104. Here again, the manipulation is especially simplified in that the lug 11.rnay either move vertically along the guide surface 105 or be automatically cammed along the guide surface 106 so as to pass through the throat 109 and into the unimpeded transition zone 107.

With thelug 11 having been moved from the phantom line position 11a, shown in FIGURE lf, to the phantom line 11b shown in this figure, lefthand or counterclockwise rotation may be imparted to the cylinder 4 so as to cause the lug 11b to translate to the left through the zone 107, viewing the apparatus as shown in FIGURE 1f. During this transition, the lug shown in the position 11C, may be cammed or guided by the slot peripheral surface 108 enroute to the lower slot 90.

By picking up on the conduit string 3, when the lug 11 has moved to the terminal position 11d adjacent the surface 98, as shown in FIGURE 1f, the lug 11 will be caused to engage the lower end 91 of the slot 90. With this engagement between the lug 1 and the slot end 91, the raising or lifting force exerted on the conduit string 3 will be transmitted to the mandrel 8. This lifting force will cause the cross bar 68 to move upwardly and raise the slip segments 44 away from wedging cooperation with the slip expanding surface 31. Additionally, the upper check valve 56 will be opened.

Thus, continued upward force exerted on the mandrel means will cause the cross bar 68, through engagement with the slot ends 79, 80, 81 and 82 to raise the bridge plug upwardly through the well bore. The open valve 56 will prevent swabbing action and the raised slip assembly will ensure inadvertent resetting of the bridge plug during the raising action.

SUMMARY OF ADVANTAGES AND SCOPE OF INVENTION The control slot 12 is uniquely configured so as to provide a simplified and virtually foolproof control network for effecting movement of the bridge plug through a well bore while disabling the bridge plug setting components.

The arrangement of the control slot further enables the setting of the bridge plug to be tested by way of simple manipulations with an operator being sure of the relative positioning of the lug 11 within the slot 12.

If it should become appropriate during the lowering operation to impart rotary movement to the conduit string 3, some such rotary movement may be effected, while maintaining the force transmitting contact between the lug 11 and the surface 96, but without imparting undesired rotation to the mandrel 8.

The transition between the lowering position shown in FIGURE 1d and the testing position shown in FIG- URE le is effected without complex zigzag motions of the conduit string 3 and involves, instead, a simple circumferential translation followed by a simple direct linear movement of the cylinder 4.

In the event that setting of the bridge plug should be desired to be intentionally effected after the plug has been raised within a well bore, the transition of the lug 11 from the disabling slot 90 to the testing slot 89 is similarly easily effected without zigzag motions of the cylinder 4 and its associated conduit string.

Since the control slot 12 has a fully uninterrupted periphery, and especially since the guide surfaces and 98 are uninterrupted, an operator can be relatively certain of the position of the lug 11. By merely rotating the cylinder 4 until resistance to movement is encountered, the operator will be able to quickly determine that the lug 11 is positioned either adjacent the surface 105 or the surface 98, depending upon the direction' of cylinder rotation. It is significant to note that this checking of the position of the lug 11 may be easily and immediately effected in view of the unimpeded interior of the transition zone 107.

The coupling and uncoupling of the cylinder 4 from the mandrel 8 is effected with particular ease. The essentially vertical entry path for the lug 11 through the mouth 104, coupled with the circumferential guiding provided by the surface 106, enables the lug 11 to be moved into the transition zone 107 with particular ease. Similarly, the straight exit path for the lug 11, passing through the throat 109 and the mouth 104, enables the cylinder 4 to be separated from the lug 11 with maximum ease.

Where the single control slot 12 is employed, having a mouth 104 extending entirely about the circumference of the sleeve 4, the centering pad 112 ensures that the receiving head is centered as it enters the cylinder interior. This serves to prevent either jamming or breaking of the lug 11.

It is also significant to note that the lug 11 may be moved from either the FIGURE 1f or the FIGURE 1d position to the FIGURE 1e position, with the lug 11 translating through the unimpeded transition zone 107. This enables an operator to position the lug in the testing slot 89, with there being virtuallyno possibility of inadvertently causing undesired mandrel or bridge plug rotation. However, at any time, an operator may rotate the slot-carrying cylinder 4 in any direction of rotation, depending upon operational requirements and exigencies that might develop in connection with a bridge plug setting, testing or retrieving operations.

In describing the invention, reference has been made to a preferred embodiment. Those skilled in the bridge plug and `well tool manipulating art will recognize that, in many instances, apparatus components have been simplied or schematically shown in order not to obscure the basic inventive aspects. However, it will be recognized that those familiar with this embodiment, and skilled in the art, may envision additions, deletions, substitutions or other modifications which would fall within the purview of the invention as set forth in the appended claims.

I claim:

1. An apparatus for use in a well bore, said apparatus comprising:

transporting means for moving well tool means through a well bore, said transporting means including:

body means having a longitudinal axis disposed to ,extend generally longitudinally of a well bore in which said apparatus is located, said body means being operable to detachably engage lug means carried by said well tool means,

first slot means operable to telescopingly receive said lug means, said first slot means being disposed to extend generally longitudinally of said well bore,

second slot means operable to telescopingly receive said lug means, said second slot means being disposed to extend generally longitudinally of said well bore,

generally L-shaped guide means extending between said iirst and second slot means,

said generally L-shaped guide means including uninterrupted, first guide means extending generally circumferentially of the longitudinal axis of said body means and generally aligned with a plane extending transversely of the longitudinal axis of said body means,

said generally L-shaped guide means further including uninterrupted second guide means extending generally longitudinally of said well bore and from said iirst guide means, when said apparatus is disposed in said well bore, and extending directly into said second slot means,

said first guide means providing uninterrupted guide means operable, throughout its entire circumferential extent, to transmit force from said operating means to said lug means, with said transmitted force being operable to induce movement of said lug means,

uninterrupted third guide means extending erally longitudinally of said well bore,

uninterrupted fourth guide means displaced circumferentially from, and converging continuously toward, said third guide means,

means permitting generally unimpeded, relative rotational movement between said body means and said well tool means, with movement of said lug means, relative to said second and gen- third guide means, occurring along a path generally aligned with said plane extending transversely of said axis of said body means. 2. An apparatus for use in a well bore, said apparatus comprising:

well tool means; well tool actuating means; disabling means for disabling said well tool actuating means; said well tool disabling means including:

tool disabling mandrel means movable generally longitudinally of said well tool means and having a longitudinal axis disposed to extend longitudinally of a well bore within which said apparatus is disposed, lug means carried by said mandrel means and projecting generally transversely outwardly thereof; transporting means for moving said well tool means through a well bore, said transporting means including cylinder means having a longitudinal axis disposed to extend generally coaxially of said mandrel means axis when said apparatus is located in said well bore, said cylinder means being operable to detachably engage and telescopingly receive said mandrel means and lug means, rigid connecting means operable to connect said cylinder means with a conduit string for rotary movement about said axis in opposite rotary direction, in response to selective rotary movement of said conduit string, first slot means operable to telescopingly receive said lug means, said first slot means being disposed to extend longitudinally of said well `bore and being operable to permit longitudinal movement of said cylinder means relative to said telescopingly received lug means but substantially prevent relative rotary movement between said cylinder means and said lug means, second slot means operable to telescopingly re ceive said lug means, said second slot means being disposed to extend longitudinally of said well bore and being operable to permit longitudinal movement of said cylinder means relative to said telescopingly received lug means but substantially prevent relative rotary movement between said cylinder means and lug means, said second slot means being disposed generally beneath said iirst slot means when said apparatus is disposed in said well bore, generally L-shaped guide means extending between said iirst and second slot means, said generally Lshaped guide means including uninterrupted, iirst guide means intersecting said first slot means and extending generally circumferentially of the longitudinal axis of said cylinder means and generally aligned with a plane extending transversely of the longitudinal axis of said cylinder means,

said generally L-shaped guide means further includ 15 uninterrupted third guide means extending upwardly from said entry means, when said apparatus is disposed in said well bore, and disposed in generally parallel alignment with said axis of said cylinder means, uninterrupted fourth guide means extending upwardly from said entry means, when said apparatus is disposed in a well bore, and converging continuously toward said third guide means, said third and fourth guide means terminating above the base of said second slot means 4when said apparatus is disposed in said well bore, means permitting generally unimpeded, relative rotational movement between said cylinder means and said mandrel means, with movement of said lug means, relative to said second and third guide means, occurring along a path generally aligned with said plane extending transversely of said axis of said cylinder means. 3. An apparatus for use in a well bore, said apparatus comprising:

well packer means including:

generally cylindrical body means, and fluid responsive seal means projecting outwardly of said body means and operable to sealingly engage the wall of a well bore; well tool actuating means including: 4

slip means mounted telescopingly on said body means and operable to wedgingly engage said body means and said wall of said well bore in response to movement of said body means in said well bore relative to said slip means; disabling means for disabling said well tool actuating means said well tool disabling means including:

mandrel means movable generally longitudinally of said packer body means and having a longitudinal axis disposed to extend longitudinally of a well bore within which said apparatus is disposed, abutment means operable to engage said body means and said slip means and prevent said wedging engagement therebetween, and lug means carried by said mandrel means and projecting generally transversely outwardly thereof; transporting means for moving said well tool means through a well bore, said transporting means includ- 111g cylinder means having a longitudinal axis disposed to extend generally coaxially of said mandrel means axis when said apparatus is located in said well bore, said cylinder means being operable to detachably engage and telescopingly receive said mandrel means and lug means, rst slot means operable to telescopingly receive said lug means, said lirst slot means being disposed to extend longitudinally of said well bore and being operable to permit longitudinal movement of said cylinder means relative to said telescopingly received lug means but substantially prevent relative rotary movement between said cylinder means and said lug means, second slot means operable to telescopingly receive said lug means, said second slot means being disposed to extend longitudinally of said well bore and Ibeing operable to permit longitudinal movement of said cylinder means relative to said telescopingly received lug means but 16 substantially prevent relative rotary movement between said cylinder means and lug means, said second slot means being disposed generally beneath said first slot means when said apparatus is disposed in said well bore, and being operable to accommodate telescoping movement of said lug means therein suicient to cause said cylinder means to abuttingly engage said packer body means, generally L-shaped guide means extending between said rst and second slot means, said generally L-shaped guide means including uninterrupted, irst guide means intersecting said rst slot means and extending generally circumferentially of the longitudinal axis of said cylinder means and generally aligned with a plane extending transversely of the longitudinal axis of said cylinder means, said generally L-shaped guide means further including uninterrupted second guide means extending generally downwardly from said rst guide means, when said apparatus is disposed in said well bore, and extending directly into said second slot means, said rst guide means providing uninterrupted guide means operable, throughout its entire circumferential extent, to transmit force from said operating means to said lug means, with said transmitted force being operable to induce well tool disabling movement of said mandrel means, lug entry means disposed longitudinally beneath said rst slot means when said apparatus is disposed in said well bore, uninterrupted third guide means extending upwardly from said entry means, when said apparatus is disposed in said well bore, and disposed in generally parallel alignment with said axis of said cylinder means, uninterrupted fourth guide means extending upwardly from said entry means, when said apparatus is disposed in a well bore, and converging continuously toward said third guide means, said. third and fourth guide means terminating above the base of said second slot means when said apparatus is disposed in said well bore, means lpermitting generally unimpeded, relative rotational movement between said cylinder means and said mandrel means, with movement of said lug means, relative to said second and third guide means, occuring along a path generally aligned with said plane extending transversely of said axis of said cylinder means, 4. An apparatus as described in claim 3 and further including:

mandrel centering means disposed in said lug entry means and operable generally axially to center said mandrel means within said cylinder means.

References Cited UNITED STATES PATENTS 2,218,988 10/1940 Johnston et al. 166--240 X 2,389,869 11/1945 Phipps 166-240 3,329,209 7/ 1967 Kisling 166-128 JAMES A. LEPPINK, Primary Examiner U.S. Cl, X.R, 

